Previously, I had assumed that FProperty::InitializeValue() would initialize a simple member (eg. a float) to the correct value, but this appears not to be the case, rather values are zero-initialized and the CDO stores the correct default values. In the case of structs, InitializeStruct() does in fact initialize correctly.
However, this means that we can't use GetMutableDefault() to get an instance of the UObject, since then we're changing what we're diffing against and serialize no values. Changed the usages of this pattern to use singletons instead.
#jira UE-141150
#review-19900014 @lauren.barnes, @aditya.ravichandran
#preflight 6267fa44a021c91a50f26a65
[CL 19919719 by sebastian nordgren in ue5-main branch]
Setters and getters are native functions called by FProperties when setting property values with *_InContainer functions.
Setters and getter function names can be manually specified with Setter = Func and Getter = Func keywords inside of UPROEPRTY macro but they will also be automatically parsed if the name is not explicitly specified if the setter or getter function name matches SetPropertyName and GetPropertyName pattern.
The latter behavior can be disabled in UHT's DefaultEngine.ini by setting AutomaticSettersAndGetters=False.
ImportText and ExportTextItem functions have been deprecated and should be replaced with *_InContainer or *_Direct variants.
#rb Steve.Robb
#preflight 6210a377a83e0bcefd03d9e1
#ROBOMERGE-OWNER: marc.audy
#ROBOMERGE-AUTHOR: robert.manuszewski
#ROBOMERGE-SOURCE: CL 19070318 via CL 19098059 via CL 19104650 via CL 19104661 via CL 19110012
#ROBOMERGE-BOT: UE5 (Release-Engine-Staging -> Main) (v921-19075845)
[CL 19147839 by marc audy in ue5-main branch]
